Fighter Sizing

[PFVA63]

Hi,

The thread on miniature carriers has brought up some questions that have always dogged me concerning small craft in general and fighters in particular.

In general, when I look at the basic Rampart fighter I think I've seen different numbers listed for its size ranging from 10 dton to 15 dton. In addition its not clear to me whether this is meant to be a measure of the actual enclosed volume of the craft, the amount of space required on a parent ship to house this craft in a close fitted/conformal bay, or if its meant to represent a bounding box (LxWxH) that the small craft can fit within on a larger ship, perhaps including space for clearances and the like, or something else.

If you look at the images for this fighter as drawn in "Azhanti High Lightning" (AHL) and make some assumptions you can end up with different answers on just how big the fighter actually is.

Specifically, I traced out the shape of the fighter based on an image from the AHL maps to estimate the total enclosed volume. In doing this I assumed that the cross sections of the fuselage were circular in shape and that the wings and fins were about 0.1m (~4in) in average thickness. In doing so, I came up with an enclosed volume of about 1.7 dton (assuming 14 cubic meters per dton). I suppose we could round this to 2 dton to give a little margin for any stuff I may have missed (such as landing skids) or under estimated (such as the thickness of the wings and fins), etc.

If you assume that the craft can fold its wings to fit within a 3m diameter tube (as used for the launching tube on the AHL) I think you come up with a space that the fighter can fit within of about 5.9 dtons.

If however, you assume a bounding box equal to the craft's length, width and height, I think you come up with about 11.63m x 4.2m x ? for the craft with the wings and fins unfolded, or 11.63m x 3m x 3m(?) assuming that the wings and fins all fold similarly to when the craft is in the launch tube.

So when folded up I think that equals about 105 cubic meters or 7.5 dtons. Unfolded, I'm not fully sure of though, since I don't have a profile of the craft, and thus can't be sure of its unfolded height. If we assume 3m for height then we have about 146.5 cubic meters or about 10.5 dtons. However, a height of 3m may be an issue if trying to fit this craft on a small ship, since I believe the assumption is that most decks are about 3m tall, but (at least according to the game "Snapshot") some of that space might be dedicated to structure and services (such as electrical cabling, piping, and vents, etc). additional you probably also need to allow for a bit of clearance between the fighter and the ship's surface to allow the small craft to be moved around without scraping any thing on the ship.

In my early edition of Traveller, I believe that there is a statement that the volumes listed for carried craft are those required to fit the small craft on the larger ship and thus may be either a bounding box or the size for a conformal bay, however this early edition of Traveller does not appear to mention fighters at all. As such, an enclosed volume for a 10 or 15 dton "craft" may only be about 2 dtons, as I estimated for the Ramparts in AHL, and the 10 (or 15) dtons listed as its size may allow for all the extra space around the craft to allow it to fit into a hangar. However, in later additions of the rules, I believe that this wording may have been changed, and sometimes you'll see references to the need to account for 110% (or more) space when carrying small craft.

In addition, when you look at stuff like Trillion Credit Squadron and High Guard, the small craft design rules in there actually kind of seem to make it look like the volume requirements may actually represent the internal required volume within the small craft. Specifically, a requirement for X dton of fuel, or Y dton of maneuver drive kind of make me think that they mean the hull of the small craft has to house something of these specific sizes.

Beyond even this though, is another issue. Specifically, if I assume that 10 dtons is the size of a bounding box for a fighter, and then make my hangar bay 15 times this size to notionally allow the ship to carry 15 of these small craft, is that hangar really all that usable. Specifically, if the bounding box for my fighter is 3m with a length 10m and a height of 3m, this box equals about 15 dton, and I can arrange them 3 wide by 5 long giving me a hangar 9m wide by 50m long and 3m high.

However, is this really a viable layout. Is there enough space between all the fighters for the pilots, armorers, and maintainers to get to them? How do I get at one of the fighters in the middle to do work on it? Do we assume that the whole hangar is just one conveyor belt where returning fighters enter at the rear and whichever one(s) which are to lunch next are the three at the front of each line? Do we assume that the entire hangar may be exposed to vacuum when launching and recovering? Do we assume that there is some sort of force field protecting the ends that a launching or recovering craft can cross, but which otherwise holds in the atmosphere, etc? Or do we assume that the entire top (or bottom) of the hangar opens to let any specific fighter we want to launch or recover?

Its alot of stuff like this (as well as some other issues) that makes me question the real validity of trying to make a small ship into a carrier just by saying the notional size of a fighter is X dtons and I've provided 15X in space therefor my ship is a carrier capable of launching and recovering 15 craft.

I guess then it would be helpful to me if anyone can point to specifics in the rules that clarify whether a small crafts dtons listing is meant to represent its enclosed volume, its space requirements based on the assumption of a conformal bay, its bounding box volume, or other (such as a mix of the above). Once that is clarified then it would be interesting to see how some of the other issues can be addressed.

Anyway, just some comments and questions.

Regards

Pat

 

[Matt123]

The flaw is in attempting to reverse engineer an image to see "if it matches" the stated dtons for a vehicle. Pretty pictures are nice but don't count on them being true to Traveller "reality".

The dtons stated for all small craft are the internal volume of the craft. As you note, the "bounding box" may be significantly greater than that. If you require an open plan hanger capable of receiving, maintaining and launching a variety of small craft, then yes you need to supply a much greater hanger space than the minimum 1:1 ratio allowed for in the rules. I would suggest a 2:1 ratio, but there is nothing hard set in CT at least. To get a BSG (Battlestar Galactica or for that matter any Starwars scene) feel I'd suggest a 10:1 or 20:1 ratio or greater for the largest craft expected to use the hanger..

Note the rules (HG & IIRC Book 2) give you a minimum 1:1. There is nothing preventing you allocating more hanger space. And the 1:1 ratio works only if the cavity is custom made for the small craft. It is intended to represent a very snug fit. Any maintenance is intended to be done elsewhere. And logic states that other craft will not fit.

For example a 1dton sphere will not fit in the same cavity as a 1dton cube (cone, cylinder, etc.).

 

[Matt123]

I should also mention the Rampart is not a great example of a fighter. In the 10-15 dton range all you get is a craft effective vs cargo ships and lightly equipped pirates.

The limiting factor is the computer size and the PP needed to power it. Most fighting ships have the best computer available for the tech level. At TL15 thats a Model 9. Lets say a Zhodani ship at TL14, thats a Model 8.

The HG mechanics give an attacks AND defence modifier for every point of differance in computer size. Meaning the Rampart vs a Zhodani combat ship suffers a -5 or -6 to hit meaning it will miss virtually all Zhodani craft once agility is factored in.

Meantime the Zhodani firing back gets a +5 to + 6 to hit, meaning it will score hits relatively easily. I'd work out better the odds, but can't remember off the top of my head what agility the Rampart has.

Space superiority Fighters need the best computer available at that tech, plus Agility-6. This makes them large. At TL12 60-70 dtons large.

 

[Icosahedron]

Hi,
In my early edition of Traveller, I believe that there is a statement that the volumes listed for carried craft are those required to fit the small craft on the larger ship. <snip> However, in later additions of the rules, I believe that this wording may have been changed, and sometimes you'll see references to the need to account for 110% (or more) space when carrying small craft.

Thanks for this heads-up. I'd never noticed that '77 statement.

You're right, on p15 of LBB2 (1977) it states:
"The several possible vehicles are indicated by the ship's vehicle table which shows the tonnage required to be devoted to hangarage or stowage..." (Small craft are listed as Ships Vehicles).

However, on p17 of the same book, it lists each of those 'non-starships' with a descriptor: "displaces XX tons".

It seems this is the basis of the original confusion over the whole '10dT vessel fits in a 10dT hangar' issue.

On p32 of LBB5 (2ed) it states that "Ships vehicles require tonnage (at no cost) equal to their own mass within the hull."
It goes on to say that small craft (the term 'vehicle' is more restricted in LBB5) require their own tonnage aboard ships of 1000dT and under, and 130% of their mass within larger ships, whilst 'big craft' require 110% of their mass in all carriers.

This wording also introduces (or perpetuates) the confusion over 'mass' and 'displacement volume'.

Basically it seems that, in the early days, the rules writers hadn't really thought it through, and attempted a retcon in LBB5 that didn't work because, firstly, many of the ships in LBB2 simply didn't have the space to carry the small craft they were allocated and, secondly, they still hadn't thought it through.

 

[dean]

I is my opinion that the small craft are assume to require 100% of their size on small ships because, as a condition of the relative size of the vessels, any small craft carried would effectively be at the outer skin of the carrying vessel and kind of in a conformal-shape dimple.

This would effectively mean the smaller craft is accessed though a mated hatch arrangement, and the outer skin would not be wholly accessible to personnel from with the carrying craft.

Larger vessels, and "military" craft in particular, would indeed need to have access to the entire vehicle for maintenance and repairs, so are therefor carried completely within the hull. "Small craft" less than 100 dtons require 30% overage for hangar spaces, and larger craft (>100 dtons) need 110%; here again it makes sense that a larger size carried craft would be closer to the outer skin of the ship and would need less internal space, as ships of these sizes would likely require the services of a shipyard for maintenance and repair. In addition, having these craft further in would make the use of a "launch tube" arrangement prohibitively displacement efficient.

Fighter size craft, OTOH, need more space because they are serviced internally by the ship's crew. In addition, with the way the launch and recovery rules are written, it makes much more sense for fighter sized craft to be used with the launch tube rules, and therefor a more reasonable assumption of interior hanger spaces.

Once again, my opinion, FWIW.

 

[kilmore]

I should also mention the Rampart is not a great example of a fighter. In the 10-15 dton range all you get is a craft effective vs cargo ships and lightly equipped pirates.

The limiting factor is the computer size and the PP needed to power it. Most fighting ships have the best computer available for the tech level. At TL15 thats a Model 9. Lets say a Zhodani ship at TL14, thats a Model 8.

The HG mechanics give an attacks AND defence modifier for every point of differance in computer size. Meaning the Rampart vs a Zhodani combat ship suffers a -5 or -6 to hit meaning it will miss virtually all Zhodani craft once agility is factored in.

Meantime the Zhodani firing back gets a +5 to + 6 to hit, meaning it will score hits relatively easily. I'd work out better the odds, but can't remember off the top of my head what agility the Rampart has.

Space superiority Fighters need the best computer available at that tech, plus Agility-6. This makes them large. At TL12 60-70 dtons large.

That depends on your defense philosophy. Six 10 ton fighters will have six weapons hardpoints while a 60 ton fighter will have one.

 

[sabredog]

Thanks for this heads-up. I'd never noticed that '77 statement.

You're right, on p15 of LBB2 (1977) it states:
"The several possible vehicles are indicated by the ship's vehicle table which shows the tonnage required to be devoted to hangarage or stowage..." (Small craft are listed as Ships Vehicles).

However, on p17 of the same book, it lists each of those 'non-starships' with a descriptor: "displaces XX tons".

It seems this is the basis of the original confusion over the whole '10dT vessel fits in a 10dT hangar' issue.

On p32 of LBB5 (2ed) it states that "Ships vehicles require tonnage (at no cost) equal to their own mass within the hull."
It goes on to say that small craft (the term 'vehicle' is more restricted in LBB5) require their own tonnage aboard ships of 1000dT and under, and 130% of their mass within larger ships, whilst 'big craft' require 110% of their mass in all carriers.

This wording also introduces (or perpetuates) the confusion over 'mass' and 'displacement volume'.

Basically it seems that, in the early days, the rules writers hadn't really thought it through, and attempted a retcon in LBB5 that didn't work because, firstly, many of the ships in LBB2 simply didn't have the space to carry the small craft they were allocated and, secondly, they still hadn't thought it through.

I actually think the rules from HG worked out pretty well for hangar space.

HG has the different requirements for hangar size: 100% of tonnage if small craft on board a ship of 1000 or less tons...130% if more than 1000 tons.

Carried ships of more than 99 tons use 110% tonnage for a hangar.

Carriers that are dispersed structure have all their carried craft on the outside and so regardless of size those craft take up space equal to their size.

The issue for vehicles is pretty minor - I use the 110% rule for any vehicle over 10 tons. That means the big tanks, subs, and other specialty vehicle that you could argue needs more than just a locking cradle to hold it in place is something that needs a little more space to accommodate the large volume - and especially the unusual shape it might have. I use as a rule of thumb: could it fit in a rectangular garage, or does it need some specialized parking arrangements?

 

[mike wightman]

That depends on your defense philosophy. Six 10 ton fighters will have six weapons hardpoints while a 60 ton fighter will have one.

Six weapons that can never hit vs 1 weapon that can hit?

 

[Andrew Boulton]

Space superiority Fighters need the best computer available at that tech, plus Agility-6. This makes them large. At TL12 60-70 dtons large.

I just squeezed a TL12 missile fighter into 40dt, but that's still pretty huge.

 

[Andrew Boulton]

Displacement vs bounding box is a huge problem for anyone making models or deckplans. T4 has more sensible hangar sizes - minimum 2x volume, 4x if you want to do any maintenance etc - but even that isn't enough sometimes.

 

[Matt123]

Six weapons that can never hit vs 1 weapon that can hit?

lol, you beat me to it!

Kilmore, I suggest you try running the numbers. No, second thoughts, I have the time.

A flight of 6 Ramparts, costing 199.2MCr, missile armed (3 launchers giving missile factor 3, not 4 as listed in JTAS 27), Agility 6, Small size (giving a -2 defensive modifier) and Computer 2bis (which = computer size 2, not 3).

A single TL15 49 ton fighter, costing 159.1MCr (before discounts), missile armed (3 launchers, missile factor 3), Agility 6, Small size, Computer 9 and it has a bridge.

Ramparts first.
6 Missile-3 batteries needing 5+ to hit. Modifiers are relative computer size (2 vs 9 =) -7, target agility rating -6, target size modifier -2. The Ramparts need to roll 20 or better on 2d6 in order to score a hit.

The single 49ton fighter fires (all firing is simultaneous...)
1 Missile-3 battery needing 5+ to hit. Modifiers are relative computer size (9 vs 2 =) +7, target agility rating -6, target size modifier -2. The 49ton fighter needs to roll 6 or better on 2d6 in order to score a hit.

The maxim "Quantity has a quality all of its own" does not hold when one side cannot hit the other.

**Edit, just removed referances to the Rampart not having a bridge. I just tried replicating the design and after scratching my head on the PP21 (M) and Armour-19 (K), the only certain thing I can say is that there is definitely room for the Rampart to have a 4 ton bridge in its 20 tons. But that design is pretty poor... *** end edit ***

 

[McPerth]

Being mostly MT player I must state I guess it's clearer than HG about those questions.

In MT the minimal size for a small craft to be useful in deep space (using thrusters instead of gravitic vehicle rules) is 20 dton. Less than that use the same rules as a gravitic vehicle does. If using HT One Small Step rules (also apeared in Challenge, sorry, I cannot remember now which number) you can also use fusion reaction drives (other propulsion systems are too slow to be useful)

Also in MT (RM, page 82), it's quite clear that the hangar must be larger than the craft on it. It specifies that you need 1.5 the craft's volume for vehicles (20 dton or less), 1.2 for mall crafts (20 - 100 dton) and 1.1 for spaceships and starshps (100 dton and over). Irregular configuration ships are an exception, as they can carry their subordinate crafts externally.

The doubts this leaves to me are:

-what about subordinate crafts exactly on the border line (e.g. the launch, exactly 20 dton)

-can a ship with a configuration other than irregular have an external subordinate craft? if yes, how is it counted in this aspect? (e.g. Gazelle's gig).

Of course, ships designed as carriers use more volume for their fighters, as they need the rapid launch facilities if they intend to be really useful in combat.

 

[Matt123]

I just squeezed a TL12 missile fighter into 40dt, but that's still pretty huge.

The tightest I can get is 53.33 ton. And thats giving it only 1ton of fuel and a fractional power plant. Also includes a bridge, computer-6 and agility-6.

 

[PFVA63]

Hi

Thanks for all the feedback.

I've been messing around with some calcs to try and figure out what a minimum hangar might look like on a small carrier based on my understanding of the original CT rules as well as based what I think might actually be more logical for comparison.

For this I've started with the general specs for a 2000 dton small carrier that I think Aramis originally posted in the "Miniature Carrier" thread, and I have assumed that the dton size of a fighter represents the bounding box that the craft would fit in, including some small allowances for clearances . Here it was assumed that the ship carried eighteen 10dton fighters for a total hangarage of 180 dtons (no additional percentages appear to have been added since, I believe, these calcs were based on the early CT rules (pre-HG).

To make things simple, lets assume that there is a standard 10 dton fighter that we wish to carry, and its bounding box is 3 deck squares wide by 6.67 deck square long, and one deck in height (equating to 20 deck squares or 10 notional dtons).

If we assume that the hangar is 9 deck squares wide by 40 deck squares long and 1 deck in height, we get 360 deck squares (or 180 notional dtons) as shown below. These dimensions will allow the housing of exactly six rows of fighters in three columns, or 18 total fighters. However, there is little i the way of access to the fighters which may greatly impact how the pilots get onboard them as well as how the fighters may be rearmed or repaired and maintained. Additionally, depending on how the fighters enter and exit the hold, the ability to launch a specific fighter may be quite limited.

If I were to just go by the base rules, little is said about accesses and airlocks and such, so that if I wanted to I guess I could assume that the hold is kind of like an egg crate, where the entire top opens up and any specific fighter can be plucked out of its resting space. I guess that this would assume that either the entire hangar becomes one big airlock or that there may be some sort of force field that holds the air in while letting the fighter pass through (I suggest this mainly because in some movies and TV shows (such as some of the Star Trek and Star Wars stuff) the use of such a force field kind of appears to me what may be happening).

Part of me though thinks that this probably isn't realistic (realizing of course that we are talking about a game and all). It just seems to me that assuming such a large space to be one large airlock, or assuming that a 2000 dton ship would be able to accommodate a 13.5m x 60m opening in its shell just seems to me to be probably not a reasonable way to do things.

An alternate option would be to assume that either the forward or aft bulkhead is a large door. This would make for a smaller hull opening ( 13.5m x 3m (or a little less if you consider that the clear deck height may be less than 3m due to deck structure etc)). Here, you could either assume a force field (as above) to keep the air in, or you could assume a full width airlock at the end of the hangar capable of holding one complete row of fighters, as shown below. I using an airlock, then 3 fighters would be regularly housed within this space, but you would still be able to fit the 18 fighters in the 180 dton space.

Unfortunately, such an arrangement would still have problems with regards to access, rearming, and maintaining/repairing the craft. Additionally, with a door only at one end, you'd probably end up either having to back the fighters on or off the craft at some point, as there really doesn't seem to ba an ability to spin the craft around inside the hangar since the hangar is only sized to exactly fit the full complement of craft. (I supposed that you might be able to spin some around while the hold is only partially full, but not all of them).

An alternate arrangement might then be to provide doors or airlocjks at both ends of the hangar. This way fighters can enter through the back and exit the front without any need to turn. Unfortunately you still end up with alot of the problems listed above, and you kind of have a conveyor belt (or Pez dispenser) type arrangement where you can't launch one of the middle craft in the hold without launching some of the fighters in front of it to clear the path. This may be an issue if say for instance if you have different mixes of laser armed and missile armed fighters onboard, though it would also be an issue if say one of the fighter is damaged and not available for launch, in which case it might be difficult to work around that craft to launch the fighters stowed behind it.

An alternative arrangement could also be to reduce the size of the main hanger to house only 16 fighters (160 dtons) and then add a single 10 dtons air lock at the front and back of the hold so that you are only launching and recovering one fighter at a time (reducing the volume of the airlock and size of the hull openings), as shown below. In this case the airlocks would actually also serve as hangar space for one fighter each so that the total space dedicated to fighter stowage is still only 180 dtons for the 18 total fighters. However, many of the other problems mentioned above still remain.

One thought I then had was to retain the single airlock fore and aft, and then make the rest of the hangar 9 deck squares wide by about 34 square long, with a little extra length added to one side as shown below.

This should allow for three columns in the hangar by 5 rows. The thought here is that you could stow 5 fighters in both the left and right columns but the center column may normally house two fighters (maybe one in the forward most position as the ready launch craft and maybe the other far aft). By having the three center spaces blank it might hopefully make access to most of the fighter a little easier and also aid in shifting the craft around if needed.

A final thought would be to perhaps make the center spot on the long side of the hangar a bit longer and maybe a bit taller (say 1 1/2 decks high) so that this space can serve as the main maintenance bay, housing whichever craft may need work at that time. I think that with a little shuffling (hopefully) you can shift any craft in the hangar to that space to be worked on. Also hopefully having some of the center spots normally clear might also make it possible to partially shift some of the fighters over a little while reaming them as well.

Hopefully, if I did my math right, it might be possible to keep the hangar at about 180 dtons or so, though actual normal operational would drop to about 12 fighters. Here I haven'y assumed that the fore and aft airlocks are used for stowage because its not clear how the pilots would get in and out, and it might otherwise limit launch and recover flexibility.

For pure transport operations though, I suppose that you could fill up all the spots, and the airlocks giving a total transport capacity of 17 fighters on 180 dtons.

Overall I don't think that any of these are ideal situations, and that a real carrier would probably be arranged much more cleverly, but its just some thoughts on how a small carrier might be arranged, to better give a feel for how much extra hangar space might seem needed for such a ship.

One big issue with all the arrangements discussed above is that if the hangar is intended to be flexible enough to hold different mixes of different sized craft (such as 10 15 and 20 dton craft), or even different types of similarly sized craft (say either a 10 dton fighter with a bounding box of 2.5 by 8 deck squares in addition to the 10 dton fighter suggested above with a bounding box of 3 by 6.67 boxes), then things get messier. Specifically, the airlocks would have to be sized to be able to fit any of the craft that may be carried, and the overall hangar dimensions may not match the bounding boxes of the other craft as well, leading to a less efficient use of the space in the hangar.

Specifically, the 9 deck square by 34 deck square hangar would only be able to house three columns by four rows of the 2.5 deck square by 8 deck square fighters. If we were to still try and leave some of the center spots open to allow for shifting of the craft, the total operational capacity would only be about 10 craft on about 180 dtons of space (or more since the airlock would have to be resized to also accommodate the longer but thinner fighters as well as the shorter but broader ones intially considered).

Regards

Pat

 

[Matt123]

Great post. A couple of detail to "correct", but feel free to ignore them and say so if you are, it saves bandwidth when muppets like myself reply.

A 10dton fighter is actually 10dton (HG p32 & small craft design sequence HG p34). Its bounding box will be larger than that depending on its design.

Any ship over 1000 dton must allocate at least 130% to hanger space (HG p32). The 18 10dton fighters would therefore need 234dtons for hanger space. Some of this will allow maintenance on one or two craft at a time, plus the capacity to shuffle the fighters around.

Without launch tubes, you can only launch 1 fighter every 20 minutes (HG p38). Launch tubes are 25x fighter size (HG p32) 250dton in this case and allow 40 fighters to be launched or recovered per turn (HG p38).

Overall tho', I suspect with an extra 30% space you can come up with a better hanger solution for 10dton fighters when you have 234dton to play with.

One last thing to consider, especially with smaller carriers (2000dton is small), is Dispersed Structure ships (HG p32).

Cheers
Matt

 

[PFVA63]

Hi

Thanks for the feedback. I had seen the reference to using 130% for ships over 1000 dtons, in an earlier post, but for my initial quick analyses I decided to ignore it, since I was using something that I think Aramis posted in response to the "Miniature Carrier' thread as being based on the original 3-book CT rules, as my starting point, since I didn't have time to try and put together my own attempt at a design.

In general, I agree that an increase in area (such as the 130%) makes alot of sense to me, especially since its hard for me to see how the pilots, maintenance crew, and armorers would even get through a hangar if the space available was exactly equal to the space required.

With respect to a 10 dton fighter being equal to 10 dtons of internal volume, that too is also what I would assume based on High Guard and Trillion Credit Squadron. However, since my early copy of the original three books suggests that the volumes listed for some stuff in there was the volume required to carry that item (eventhough fighters weren't addressed) I figured that I'd start with that assumption for now. I'd really like to try and take a closer look at something more reasonable later. But I would need to design up a fighter for use in High Guard and then try and sketch up what it actually looks like in CAD. I have some early attempts at something like that from awhile ago, so maybe I can dig them up as a starting point later.

I had forgotten about the one fighter launch at a time, unless you're using launch tubes, but that makes alot of sense. And it makes the assumption that a small ship may only have a single craft sized airlock fore and aft seem more likely.

For such a small ship though I suspect that launch tubes probably wouldn't make sense.

Maybe some day, if I can get a handle on all the issues, it might be worthwhile to try and draw up a larger carrier to see if I can make something that makes sense (to me) while still meeting the space requirements of the rules.

Thanks for your feedback.

Regards

Pat

 

[kilmore]

Okay then, as it stands, there's really no reason for the Rampart fighter to exist other than to mop up after the big boys. I realize there's nothing in the rules for this, but with TL 15 computer tech do you think there would be a program that would allow the Rampies to swarm around the home ship or something like a big space Growler and benefit from their higher computer level?

Maybe a computer program that allows a computer to run at the half of the power of the original with a penalty for range?

 

[aramis]

Great post. A couple of detail to "correct", but feel free to ignore them and say so if you are, it saves bandwidth when muppets like myself reply.

A 10dton fighter is actually 10dton (HG p32 & small craft design sequence HG p34). Its bounding box will be larger than that depending on its design.

Any ship over 1000 dton must allocate at least 130% to hanger space (HG p32). The 18 10dton fighters would therefore need 234dtons for hanger space. Some of this will allow maintenance on one or two craft at a time, plus the capacity to shuffle the fighters around.

Without launch tubes, you can only launch 1 fighter every 20 minutes (HG p38). Launch tubes are 25x fighter size (HG p32) 250dton in this case and allow 40 fighters to be launched or recovered per turn (HG p38).

Overall tho', I suspect with an extra 30% space you can come up with a better hanger solution for 10dton fighters when you have 234dton to play with.

One last thing to consider, especially with smaller carriers (2000dton is small), is Dispersed Structure ships (HG p32).

Cheers
Matt

The design he's working with is PURE Bk 2... well, actually, Pure TTB. No HG at all. Not the fighter (it's in TTB), nor the mounting rules. So the fighter can be assumed to be a 10Td Bounding Box. Or is tunnel-mounted.

 

[Icosahedron]

Okay then, as it stands, there's really no reason for the Rampart fighter to exist other than to mop up after the big boys. I realize there's nothing in the rules for this, but with TL 15 computer tech do you think there would be a program that would allow the Rampies to swarm around the home ship or something like a big space Growler and benefit from their higher computer level?

Maybe a computer program that allows a computer to run at the half of the power of the original with a penalty for range?

A few of you seem to be making the assumption that the only purpose for a 'fighter' is to dogfight other fighters. In fact, fighters (even 6 or 7 ton ones) can be used for many purposes - attacking enemy transport convoys, taking down pirates, providing air support for ground operations. The lowly 2bis is more than adequate for these duties. It has a reason to exist.

 

[Matt123]

The design he's working with is PURE Bk 2... well, actually, Pure TTB. No HG at all. Not the fighter (it's in TTB), nor the mounting rules. So the fighter can be assumed to be a 10Td Bounding Box. Or is tunnel-mounted.

Like you I only have access to the '81 version of the rules. In that the fighter is described as (Book 2, p18 & TTB p63);

Fighter: Using a 10-ton hull, the fighter is capable of 6-G acceleration...

I'm not sure how to interpret that as meaning the fighter occupies a 10-ton bounding box, but actually displaces less than 10 ton in volume. Surely a 10-ton hull is intended to mean a 10-ton hull?

Unless we are at cross purposes with what Pat means by a "bounding box". I understood him to mean the volume occupied by a theoretical box which contains all of the craft including extremities (eg: winglets, spiky thing on the nose, etc) and regardless of the actual shape of the craft. For example a sphere of x dtons and diameter y would occupy y^3 dtons, the difference between the sphere dtons & bounding box dtons being waste space. To leave no waste space would require a box shaped fighter with no extremities.

I do accept what you are saying about the 2000ton carrier being pure book 2, I probably should have checked first. *** (Pat, pure Book 2 designs can be built up to 5000 ton and hold small craft on a 1:1 basis. A 10dton fighter can be housed within 10dton, it being obviously a very snug fit. A tunnel mount or other snug arrangement, but definitely not a typical hanger. My comments assumed a High Guard design),